ALMA Chemical Evolution (ACE) survey: The gas fundamental metallicity relation at cosmic noon

@misc{langan2026alma,
  title = {{ALMA Chemical Evolution (ACE) survey: The gas fundamental metallicity relation at cosmic noon}},
  author = {I. Langan and I. Shivaei and G. Popping and L. A. Boogaard and N. N. Geesink and M. Kaasinen and A. Pope and R. Popescu and M. Solimano and L. Arriscado and D. Narayanan and M. Parente and N. Reddy and R. L. Sanders},
  howpublished = {arXiv},
  year = {2026},
  month = oct,
  doi = {10.48550/arxiv.2609.20921},
  eprint = {2609.20921},
  archivePrefix = {arXiv},
  url = {https://arxiv.org/abs/2609.20921},
}

TY  - UNPB
TI  - ALMA Chemical Evolution (ACE) survey: The gas fundamental metallicity relation at cosmic noon
AU  - I. Langan
AU  - I. Shivaei
AU  - G. Popping
AU  - L. A. Boogaard
AU  - N. N. Geesink
AU  - M. Kaasinen
AU  - A. Pope
AU  - R. Popescu
AU  - M. Solimano
AU  - L. Arriscado
AU  - D. Narayanan
AU  - M. Parente
AU  - N. Reddy
AU  - R. L. Sanders
PY  - 2026
DA  - 2026/10/07
PB  - arXiv
DO  - 10.48550/arxiv.2609.20921
UR  - https://arxiv.org/abs/2609.20921
AB  - Chemical enrichment shapes how galaxies form and evolve. The gas-phase metallicity is directly linked to the stellar mass, star formation rate, and cold gas of the interstellar medium. Thus, the cold gas fundamental metallicity relation (GFMR) is a powerful tool for probing galaxy evolution, bridging large-scale gas flows modulating the cold gas reservoir and small-scale metal enrichment tracing the cumulative impact of star formation. Constraining all these properties for the same representative sample of galaxies remains challenging yet essential. Using CO(3--2) band 3 observations from the Atacama Large Millimeter/submillimeter Array Chemical Evolution (ACE) survey, we investigated the GFMR in a sample of 26 main-sequence (log(M_*, med)=9.96), subsolar-metallicity (12+log(O/H)_med=8.44) star-forming galaxies (SFGs) at z~2. With 17/26 CO detections, including some of the lowest-metallicity CO detections at cosmic noon, we find that the stellar mass remains the primary driver of the chemical evolution in our sample (sigmaMZR~0.10). Whereas the molecular gas likely plays a secondary role (sigmaGFMR~0.11) similar to that of the star formation rate (sigmaFMR~0.13). This likely reflects our sensitivity to only the CO-bright component of the molecular reservoir. Our results remain consistent with gas-regulator models and suggest the existence of efficient molecular outflows, with an average mass loading factor of eta~4, regulating star formation and chemical enrichment.
ER  -